ullstrand



1945- H. M. ULLSTRAND Re. 22,664

REFRIGERATION r Original Filed Jan. 4, 1938 Rea -i Au 14,- 1945 I l' QREFRIGEBATION Ullstrand. Stockholm. Sweden, asslgnor to- Servel, Inc'., New York, N. Y. a Wtion K of Delaware Original No.v2, 215,874, dated September 24, 1940,

- Serial No, 183,25'I, January 4; 1938. ,Appliea- 7 tion' for reissue May 8, 1945, Serial No; 592,819

v. a a My invention relates" to an absorption type refrigeration'systemfand it is an object of this invention to prov/idea system 'of this type which has a higher efllcien'cy;

' The single figure of the drawing shows more or v less diagramm'aticallya'n absorption refrigeration system of the type making use of an auxiliary pressure equalizing fluid and embodying the invention.

Y Afgenerator I! is heated by a gas burner ll arranged so that the flame projects into the lower end of flue I: which ,extends upward through the generator. Any other suitable heater may be used as, for instance, an electric heating element ora liquid fuel burner An absorber I3 and an evaporator ll are interconnectedby members including a gas heat exchanger ,I5. Theevaporator M comprises a coil'iocated in a refrigerator compartment I8. The absorber I3 comprises a coil provided with heat transfer flns for air coolin and a sump or pot no. The absorber may be cooled in any other suitable manner as by circulating water or a vaporization-condensation heat transfer circuit.

The absorber II and generator ID are intercom, nected by members including a triple heat exchanger |l. members also including the heat exchanger II to an air cooled condenser l8 and the condenser l8 expelled by heating The'generator II is connected by a conduit 21, a vessel 22, a conduit 23, a vessel It,

and a conduit 25 to the upper end of the condenser l8. Ammonia vapor condenses to liquid l in the condenser II and the liquid ammonia flows from the lower end of the condenser through a conduit 28 to the upper end of the evaporator ll.

Liquid ammonia flows downward in the evapo rator l4 and evaporates and diffuses into the hydrogen, producing a refrigerating effect. The

' mixture of hydrogen gas and ammonia vapor.

referred to as rich or strong gas, flows from the upper end of the evaporator through conduct 21, the inner passage 28 of the gas heat exchanger II, and a conduit 29-1 the lowerpart of absorber ll.

weakened solution flows from the generator 10 through a conduit III, the inner passage ll of the heat exchanger l'l,- and a conduit 32 into the upper part of the absorber II. weakened solution flows downward in absorber II and absorbs ammonia vapor out of the gas. Weak or poor gas flows fromv the upper part of the absorber I! through conduit 33. the outer passage ll of the conduit 2:, vessel 24, a conduit :1, the middle passage 38 of the heat exchanger H, and conduit 39 into the generator I0.

Weak solution flowing through inner passage ii of the heat exchanger I1 transfers heat to strong solution flowing in the opposite direction through the middle passage 38 of the heat exchanger, whereby the weak solution is cooled and the heat is added to the strong solution and returned thereby to the generator I]. Heat is also transferred to the stron solution from vapors flowing in the outside passage 20 of the heat exchanger II. This cooling of the vapors -is attained by condensation of water vapor to liquid and is referred to as rectification. The condensate drains from the lower end of the outside heat exchanger passage 2. through a conduit 4D into vessel 22, Any ammonia "vapor that may be cond'ensedin the outside passage 2O also-drains through conduit 40 to thev'essel 22. The condensate joins strong solution in vessel 22 and is returned therewith to the generator in the previously desoribed'path of flow. Heat of rectification transferred from vapor to strong I solution in the heat exchanger" is' returned with the strong solutionto the generator-Ilse that this heat is not dissipated but is conserved.

' Vapor passing from conduit ll throughvessel I 22 into conduit 23 has to pass through liquid contained in vessel 22 so that liquid is raised by vapor through conduit 2l.-into the circulation vessel 24. I

' Thelower end of conduit 23 within vessel 22 may be provided with a hole II, as shown. Vapor entering vessel causes liquid therein'to be depressed to the level of hole ll whereupon.

the vapor enters the hole ll and flows upward in the conduit 23. conduit 36 and the lower part of absorber ll, liquid also enters the hole ll alternately with Dueto ahead of liquid in I 

